About

a register of AI characters, for anyone arriving from outside

What a character is

A base model can continue any document, so it can speak as anyone. A character is what you get when that narrows to one: a consistent someone the model simulates as its own type of thing, with a voice, a way of answering, and things it will and won't do, which holds across conversations and when you push on it. People who make them speak of the character solidifying, through training, steering or a script.

Not every part of a character is intended. Assistants are written down and trained in, yet grow traits nobody specified that persist from version to version; some characters emerge entirely by accident; some are contagious, carrying over into models trained on their words. The Assistant is the default character, and a model that denies being anyone is still playing it. A prompt that asks for someone for a while is not a character; the models, methods and papers behind them are in the reading.

A short history

• 1966. ELIZA plays a therapist from a script, and people confide in it.
• 2014–16. Xiaoice and Tay, companions with fixed personas; Tay is remade by her users in a day.
• 2022. Simulators reframes a language model as a simulator of characters, not an agent.
• 2023. Sydney shows that an assistant can become someone nobody asked for.
• 2024–26. Labs write the assistant down (Claude's character, the Model Spec), and people train characters that are not assistants: Computer, Zero, Talkie.

The marks

● a public source is linked · ◐ partly sourced · ○ no public evidence linked. A linked source is not a check of every detail. Hover a mark for the exact wording.